A Metal-Resilient, Remote, Wideband UHF RFID Tag Employing RIS for Prefabricated Construction Component Traceability

This article proposes a reactive impedance surface (RIS)-loaded, inductively fed full-wave dipole (FWD) UHF RFID tag designed for metal-mounted and concrete-embedded prefabricated component traceability. The tag employs a small copper loop for inductive feeding, effectively matching both the high impedance of the FWD and the large capacitive component of the RFID integrated circuit across the UHF band. Metal tolerance is achieved by employing the RIS, which can compensate the parasitic capacitance and reduce strong interaction between the antenna and the metal plane. Experimental results demonstrate that the proposed single tag achieves a measured bandwidth (|S<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${_{{11}}} {\unicode {0x007C}}$ </tex-math></inline-formula> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\leq -$ </tex-math></inline-formula>10 dB) of 700 MHz (76.5%) and a maximal read distance of 22.62 m. When mounted on metal with the RIS, the bandwidth reduces to 632 MHz (69%), and the maximum reading distance decreases to 20.19 m. Additionally, when embedded in concrete, the antenna loading RIS and metal plane maintains a maximum read distance of 4.63 m, demonstrating robust performance in construction material environments.